<html>
    <head>
        <script src="https://cdn.jsdelivr.net/npm/vue@2.6.12"></script>
    </head>
    <body>
        <div id="app">
            <p>{{foo}}</p>
            <button v-on:click="foo ='100'">改变它</button>
        </div>
        <script>
            var obj={
                foo:'10'
            }
            Object.freeze(obj);
                new Vue({
                    el:'#app',
                    data:obj
                })
        </script>
    </body>
</html>